Vendor import of lldb trunk r256945:

https://llvm.org/svn/llvm-project/lldb/trunk@256945

1 files changed, 27 insertions, 0 deletions

diff --git a/packages/Python/lldbsuite/test/lock.py b/packages/Python/lldbsuite/test/lock.py
new file mode 100644
index 0000000..89823b8
--- /dev/null
+++ b/packages/Python/lldbsuite/test/lock.py
@@ -0,0 +1,27 @@
+"""
+Interprocess mutex based on file locks
+"""
+
+import fcntl
+import os
+
+class Lock:
+
+    def __init__(self, filename):
+        self.filename = filename
+        # This will create it if it does not exist already
+        unbuffered = 0
+        self.handle = open(filename, 'a+', unbuffered)
+
+    def acquire(self):
+        fcntl.flock(self.handle, fcntl.LOCK_EX)
+
+    # will throw IOError if unavailable
+    def try_acquire(self):
+        fcntl.flock(self.handle, fcntl.LOCK_NB | fcntl.LOCK_EX)
+
+    def release(self):
+        fcntl.flock(self.handle, fcntl.LOCK_UN)
+
+    def __del__(self):
+        self.handle.close()